Passenger seats of automobiles or trains, various kinds of sofas, office chairs, and the like are often formed by attaching a skin material such as fiber fabric or natural or synthetic leather to the surface of a cushion body (foam body) molded in a predetermined shape by using a foaming resin material. The cushion body used in these various seats often has a curved surface composed of convex-concave shapes satisfying human engineering factors in order to maintain a seating posture which provides no fatigue despite long-hour seating.
Moreover, when a skin material is attached to the surface of a cushion body, after molding the cushion body in a desired shape, a method of covering and fixing a skin material to the surface of the obtained cushion body is often employed. In particular, in this case, a molding hook and loop fastener is generally used as means for fixing the surface of the cushion body and a rear surface of the skin material.
A molding hook and loop fastener has a configuration in which a plurality of engaging elements (male engaging elements) are disposed on one surface (first surface) of a base portion made from a thermoplastic resin, and such a molding hook and loop fastener is integrally molded so that the engaging elements are exposed to the surface of the cushion body when the cushion body is molded. Moreover, a plurality of engaging elements (female engaging elements) configured to be fastened to the engaging elements of the molding hook and loop fastener are formed on the rear surface of the skin material that covers the cushion body.
After the skin material is covered on the cushion body to which the molding hook and loop fastener is integrated, the female engaging elements disposed on the rear surface of the skin material are pressed against the male engaging elements of the molding hook and loop fastener exposed to the surface of the cushion body, whereby the skin material is fastened to the molding hook and loop fastener. In this manner, the skin material is easily fixed to the surface of the cushion body along the convex-concave shapes of the surface, and the skin material is prevented from floating from the cushion body.
In such a molding hook and loop fastener used for fixing the skin material and the cushion body, in order to stably secure required fastening strength, it is necessary to prevent a foaming resin material of a cushion body from flowing into an area (engaging element area), in which the engaging elements of the molding hook and loop fastener are formed, during the expansion molding of the cushion body to allow the engaging element area of the molding hook and loop fastener to be exposed to the surface of the cushion body.
Moreover, in such a molding hook and loop fastener, in order to fix the skin material along the convex-concave shape of the surface of the cushion body so as not to float, it is often necessary to integrally mold the molding hook and loop fastener itself to the cushion body in such a manner as to be bent in a width direction or a front-rear direction of the molding hook and loop fastener so as to match the surface shape of the cushion body.
In order to meet the above demands, a molding hook and loop fastener (locking member for mold-in molding) disclosed in JP 2004-321 A (Patent Document 1) and a molding hook and loop fastener (male surface fastener member) disclosed in JP 2010-162339 A (Patent Document 2) have been proposed, for example.
For example, as illustrated in FIG. 49, a molding hook and loop fastener 150 described in Patent Document 1 includes a linear locking portion (surface fastener portion) 151 in which a number of engaging elements 153 are disposed on a first surface of a base portion 152 and a synthetic resin foam layer 154 attached to a second surface of the locking portion 151. Moreover, the synthetic resin foam layer 154 is formed to be larger in the width direction than the locking portion 151, and a portion of the synthetic resin foam layer 154 protruding outside more than the locking portion 151 is configured as a sealing portion that adheres closely to a mold 155 when the molding hook and loop fastener 150 is placed in the mold 155. Further, in Patent Document 1, the synthetic resin foam layer 154 of the molding hook and loop fastener 150 has a thickness of 1 mm to 10 mm and initial compression deformation of 0.02 MPa to 1.0 MPa.
According to Patent Document 1, such a molding hook and loop fastener 150 is easily and reliably held in a recess 156 of the mold 155 used for molding a cushion body, and the sealing property between the mold 155 and the synthetic resin foam layer 154 of the molding hook and loop fastener 150 is excellent. Thus, it is possible to prevent a resin composition (foaming resin material) from flowing into the engaging element 153 of the molding hook and loop fastener 150. Since the molding hook and loop fastener 150 illustrated in FIG. 49 is linearly formed, it is not possible to curve the molding hook and loop fastener 150 in the width direction so as to be integrally molded to the cushion body.
Due to this, in Patent Document 1, as illustrated in FIG. 50, as a molding hook and loop fastener capable of being integrally molded to a cushion body in a state of being bent in a curved shape in the width direction, a molding hook and loop fastener 150a is also proposed in which a synthetic resin foam layer 154a is expanded and molded in a generally curved shape in advance, and a necessary number of locking portions (surface fastener portions) 151a are attached to the obtained synthetic resin foam layer 154a using an adhesive agent.
On the other hand, as illustrated in FIG. 51, a molding hook and loop fastener 160 disclosed in Patent Document 2 includes a plurality of surface fastener portions 161 having an engaging element area 165 that is surrounded by a vertical barrier portions 163 and lateral barrier portions 164 at the front and rear edges and a connecting portion 162 that connects the adjacent edges in the longitudinal direction of the surface fastener portions 161 with a predetermined gap.
Each surface fastener portion 161 includes a planar base portion 166, a plurality of hook-shaped engaging elements (male engaging elements) 167 that are erected on one surface of the base portion 166, right and left vertical barrier portions 163 that are erected on the right and left side edges of the base portion 166 along the longitudinal direction with the engaging elements 167 interposed, a lateral barrier portion 164 that is erected along the width direction between the right and left vertical barrier portions 163, protruding portions 168 that fix a monofilament that forms the connecting portion 162, and linear magnetic bodies 169 disposed along the longitudinal direction.
The plurality of engaging elements 167 disposed in each surface fastener portion 161 are arranged at predetermined intervals along the longitudinal direction and the width direction of the base portion 166. The vertical barrier portion 163 has three lines of vertical walls on each of the right and left sides, and each line of vertical walls includes a plurality of vertical walls 163a disposed at a predetermined pitch in the longitudinal direction. In this case, the vertical walls 163a of adjacent lines of wall portions are alternately disposed in a staggered form. Moreover, the lateral barrier portion 164 includes the engaging elements 167 arranged in the width direction and a plurality of lateral wall portions 164a disposed along the width direction.
The protruding portions 168 that fix the monofilament are formed so as to protrude in a block shape from the base portion 166 approximately at the center in the width direction of the surface fastener portion 161 and embed the monofilament over the entire area of the surface fastener portion 161. The linear magnetic bodies 169 disposed in the surface fastener portion 161 are fixed by having a portion of the linear magnetic bodies being embedded in a fixing portion 170 that protrudes in a block shape from the base portion 166.
The connecting portion 162 that connects the surface fastener portions 161 is formed of a linear monofilament made from a synthetic resin that is embedded in the protruding portions 168 of the surface fastener portions 161 as described above. Although this monofilament disposed in the area of the surface fastener portions 161 is embedded in the protruding portions 168, the monofilament in the gap between the adjacent surface fastener portions 161 is exposed to the outside, and a portion in which the monofilament is exposed forms the connecting portion 162. Since such a connecting portion 162 is disposed, the molding hook and loop fastener 160 can be easily bent in the width direction.
Such a molding hook and loop fastener 160 of Patent Document 2 can be adsorbed and fixed to a cavity surface of a mold so that the engaging elements 167 face the cavity surface by allowing the linear magnetic bodies 169 of the molding hook and loop fastener 160 to be attracted to the mold using the magnetic force of magnets provided in advance in the mold when the cushion body is expanded and molded using the mold.
In this case, since the connecting portion 162 (monofilament) that connects the surface fastener portions 161 can be easily bent, the molding hook and loop fastener 160 can be adsorbed and fixed to the cavity surface of the mold in a curved state in the width direction or the front-rear direction and be integrally molded to the cushion body in the curved shape.
Moreover, the molding hook and loop fastener 160 is configured such that the engaging element area 165 in which the plurality of engaging elements 167 are disposed is surrounded by the vertical barrier portion 163 and the lateral barrier portions 164. In particular, in Patent Document 2, the vertical barrier portion 163 includes a plurality of vertical walls (divided walls) 163a disposed in a staggered form at a predetermined pitch and each vertical wall 163a is arranged to be away from each other.
In this case, when the cushion body is expanded and molded, the foaming resin material tries to penetrate into the engaging element area 165 through the gap formed between the vertical walls 163a of the vertical barrier portion 163. However, since the flowing resistance of the foaming resin material increases due to each vertical wall 163a, the foaming resin material is expanded and solidified before reaching the engaging element area 165 and is thus prevented from penetrating into the engaging element area 165.
In this manner, in the molding hook and loop fastener 160 of Patent Document 2, it is possible to prevent the foaming resin material from penetrating into the engaging element area 165 by flowing over the vertical barrier portion 163 and the lateral barrier portion 164 during the expansion molding of the cushion body and to stably secure the fastening strength of the engaging elements 167 of the molding hook and loop fastener 160 that is integrally molded to the cushion body.